SOUTH SAN FRANCISCOGenentech Inc. has issued a Dear
Doctor letter to alert physicians to 62 postmarketing reports
of serious adverse events related to the use of trastuzumab
(Herceptin), the companys anti-HER-2 monoclonal antibody for
use in treating HER-2-positive breast cancer. To date, about 25,000
women have been treated with Herceptin worldwide.
The adverse events include hypersensitivity reactions, infusion
reactions, and pulmonary events. Fifteen patients had pulmonary and
other adverse events following Herceptin infusion, which led to
death. Nine had onset of symptoms within 24 hours of infusion. Most
of the patients with fatal events had significant preexisting
pulmonary compromise secondary to intrinsic lung disease and/or
malignant pulmonary involvement.
Herceptin product labeling will be modified with additions to the
warnings and adverse reactions sections.